Netmask Translation Table

This is a Netmask Translation Table. It can be used to determine what IPs should be used and which ones cannot be used.


Netmask                CIDR         Notes
=====================================================================

255.255.255.255        /32          Host (single address)
255.255.255.254        /31          Unusable

255.255.255.252        /30            4 IPs with   2 Usable
255.255.255.248        /29            8 IPs with   6 Usable

255.255.255.240        /28           16 IPs with  14 Usable
255.255.255.224        /27           32 IPs with  30 Usable

255.255.255.192        /26           64 IPs with  62 Usable
255.255.255.128        /25          128 IPs with 126 Usable

255.255.255.0          /24         256 IPs with  254 Usable "Class C"

Note: The first and last IP of a series are NOT usable and the first  
usable IP is normally set up for the router.
The 1st IP is the network address. The last IP is the broadcast address.
=====================================================================

Each customer will be given their own unique IP block necessary to configure their own network. This unique IP information will be supplied by their Account Manager.

The below is only an EXAMPLE, do NOT use its IPs, instead, use those IP numbers that come from your Account Manager.

Your Account Manager should give you all the following information.


Dear Customer:

Your IP block is 205.177.54.32/28

Gateway IP address (Router IP)      205.177.54.33
Useable IP's                        205.177.54.34-46
Subnet Mask                         255.255.255.240

DNS Servers:    ns.cais.com         205.177.10.10
                ns2.cais.com        199.0.216.222

Subnetmask Translation Table

This is a Netmask Translation Table. It can be used to determine what IPs should be used and which ones cannot be used.


Subnetmask            Subnetmask (binary)                    CIDR         Notes
=================================================================================================

255.255.255.255       11111111.11111111.11111111.11111111    /32          Host (single address)

255.255.255.254       11111111.11111111.11111111.11111110    /31          Unusable
255.255.255.252       11111111.11111111.11111111.11111100    /30            4 IPs with   2 Usable
255.255.255.248       11111111.11111111.11111111.11111000    /29            8 IPs with   6 Usable
255.255.255.240       11111111.11111111.11111111.11110000    /28           16 IPs with  14 Usable
255.255.255.224       11111111.11111111.11111111.11100000    /27           32 IPs with  30 Usable
255.255.255.192       11111111.11111111.11111111.11000000    /26           64 IPs with  62 Usable
255.255.255.128       11111111.11111111.11111111.10000000    /25          128 IPs with 126 Usable
255.255.255.0         11111111.11111111.11111111.00000000    /24         256 IPs with  254 Usable 
                                                                                "Class C"

255.255.254.0         11111111.11111111.11111110.00000000    /23         
255.255.252.0         11111111.11111111.11111100.00000000    /22         
255.255.248.0         11111111.11111111.11111000.00000000    /21         
255.255.240.0         11111111.11111111.11110000.00000000    /20         
255.255.224.0         11111111.11111111.11100000.00000000    /19         
255.255.192.0         11111111.11111111.11000000.00000000    /18         
255.255.128.0         11111111.11111111.10000000.00000000    /17         
255.255.0.0           11111111.11111111.00000000.00000000    /16         
                                                                                "Class B"

255.254.0.0           11111111.11111110.00000000.00000000    /15         
255.252.0.0           11111111.11111100.00000000.00000000    /14         
255.248.0.0           11111111.11111000.00000000.00000000    /13         
255.240.0.0           11111111.11110000.00000000.00000000    /12         
255.224.0.0           11111111.11100000.00000000.00000000    /11         
255.192.0.0           11111111.11000000.00000000.00000000    /10         
255.128.0.0           11111111.10000000.00000000.00000000    /9          
255.0.0.0             11111111.00000000.00000000.00000000    /8         
                                                                                "Class A"

254.0.0.0             11111110.00000000.00000000.00000000    /7         
252.0.0.0             11111100.00000000.00000000.00000000    /6         
248.0.0.0             11111000.00000000.00000000.00000000    /5         
240.0.0.0             11110000.00000000.00000000.00000000    /4         
224.0.0.0             11100000.00000000.00000000.00000000    /3         
192.0.0.0             11000000.00000000.00000000.00000000    /2         
128.0.0.0             10000000.00000000.00000000.00000000    /1          
0.0.0.0               00000000.00000000.00000000.00000000    /0         
                                                                                IP space



Note: The first and last IP of a series are NOT usable and the first  
usable IP is normally set up for the router.
The 1st IP is the network address. The last IP is the broadcast address.
=====================================================================

Go Back to previous link

For further assistance, e-mail our Support Department or call us.